In various surgical procedures, it is necessary to dissect bone or other tissue. Many conventional surgical instruments used for the dissection of bone or other tissue employ pneumatic or electrical motors to rotate a cutting element. In their most basic form, such surgical instruments include a motor portion having a rotary shaft, a dissection tool having a cutting or abrading element that is coupled to the rotating shaft of the motor, and a coupling arrangement for connecting the dissection tool to a spindle or collet of the rotary shaft. The spindle or collet of the rotary shaft is usually housed within a base that is attached to the motor.
Because it is frequently necessary to replace the dissection tool, a quick release coupling may be used to secure the dissection tool to the surgical instrument. An example of such a quick release coupling is shown and described in commonly assigned U.S. Pat. No. 5,505,737, which is herein incorporated by reference in its entirety. Another quick release coupling is disclosed in United States Patent Application Publication Number 2003/0023256 A1, published on Jan. 30, 2003, which is herein incorporated by reference in its entirety.
Powered surgical dissection instruments often utilize dissection tools having small shaft diameters in relation to their length. Such shafts may bend or flail in use if not adequately supported. This occurrence may be heightened when such shafts are used with motors that are designed to reach speeds in excess of 72,000 rpm. Tool makers have provided attachments or tubes that engage the motor portion and receive a portion of the dissection tool shaft. Typically, such an attachment will include one or more bearings that support the dissection tool shaft as it extends from the tool collet. Attachments may be provided with many configurations varying by length, diameter and function.
Sometimes it is desired to vary the distance between a distal end of an attachment tube and a tissue dissection head on a dissection tool. In such cases, a telescoping attachment tube may be used. An example of a telescoping attachment tube is disclosed in U.S. patent application Ser. No. 10/326,178, filed on Dec. 20, 2002, which is herein incorporated by reference in its entirety.
A need exists in the pertinent art for an improved surgical tool which permits an angled attachment of the tool relative to the motor.